1. Field of the Invention
The invention relates to a rotary cutting tool, in particular a drill, comprising a shank and an interchangeable cutting tip which can be coupled to the shank in a form-fitting manner.
2. Background Information
An example of a known cutting tool having an interchangeable cutting tip is described in WO 2006/046227 A1. The cutting tips, as soon as they have become severely worn, are removed from the shank in a nondestructive manner using a tool and are replaced by a new cutting tip. The cutting tip is fastened by means of form-fitting locking, similar to a bayonet catch, in which an undercut against the direction of rotation is provided in the shank, into which undercut a locking projection of the cutting tip projects during the rotary locking. The rotary movement is likewise transmitted to the cutting tip via a form fit. To absorb lateral cutting forces, a supporting surface is provided in the region of the rear-side end of the cutting tip, to be more precise in the region of the locking geometry. The cutting tip has a cylindrical section axially between the locking surface and the drill point, the cylindrical said section being at a slight distance from the shank via a gap.
EP 0 984 841 B1 shows an alternative embodiment of a known cutting tool having an interchangeable cutting tip, wherein a small, stub-like pre-centering extension projects from the rear-side end face of the cutting tip. The pre-centering extension performs the task of roughly centering the cutting tip relative to the shank.
Although generally suitable for their intended uses, there is still room for improvements in such cutting tools, particularly in improving the locking of the cutting tip in the cutting tool.